The invention pertains to a lawn care vehicle with a tool attachment that is supported by the vehicle frame.
Garden and lawn care vehicles usually contain attachments that are connected to the body of the vehicle by carrying devices. These attachments may consist of lawn care equipment, e.g., mowers with spiral or rotating blades, vertical cutters, raking devices or the like. The attachments are arranged on the body of the vehicle via the carrying devices such that their height can be adjusted, i.e., they can be moved between an operating position, whereby they are in contact with the ground, and a raised position for transport or service.
EP-A1 0,217,773 pertains to a riding lawn mower with a chassis that carries a drive unit. This drive unit drives the wheels as well as a cutting device that is separably attached to the chassis. The cutting device can be moved between a lower cutting position and an upper non-cutting position. This adjustment is realized by means of a lever arrangement that makes it possible to adjust the cutting height and completely raise the cutting device. In all these positions, the cutting device remains underneath the vehicle, i.e., the cutting device must be detached for maintenance and service purposes because it is not accessible.
U.S. Pat. No. 5,079,907 describes a riding lawn mower that contains a grass cutting device and a blade housing, both of which can be moved between an essentially horizontal mowing position and an upwardly tilted service position. The blade housing is suspended on an adjustment mechanism, one end of which is connected to the blade housing, and the other end of which is connected to the body of the vehicle. In its raised position, the blade housing is tilted toward the rear by the adjustment mechanism in order to gain access to the blades located in the housing. However, such a design can only be realized if the cutting device can be freely moved, i.e., if the cutting device is not entirely or only partially arranged underneath the vehicle.
U.S. Pat. No. 5,042,236 discloses a golf lawn mower with a total of five spiral-bladed mowing units. In this case, three spiral-bladed mowing units are arranged in front of the golf lawn mower, and two spiral-bladed mowing units are arranged laterally offset to the three front spiral-bladed mowing units, i.e., underneath the vehicle frame. This arrangement serves for mowing strips of lawn remain between the front spiral-bladed mowing units with the spiral-bladed mowing units offset such that a uniform lawn pattern can be achieved. Here, the front spiral-bladed mowing units are accessible for maintenance and service purposes, but access to the rear spiral-bladed mowing unit is very difficult.
EP-B1 0,182,229 pertains to a farm tractor with a so-called front hitch that is arranged on the frame of the farm tractor in horizontally movable fashion. The front hitch serves, for example, for accommodating a mowing mechanism, a soil cultivation device or the like. The horizontal movability makes it possible to alter the existing leverages in such a way that the front wheels can be subjected to a higher load and thus generate a higher tensile force. However, neither the front hitch nor the tool attachment carried by the front hitch is arranged underneath the farm tractor or is otherwise covered.
It would therefore be desirable to improve the accessibility of the tool attachments in known garden and lawn care vehicles.
The present invention provides a vehicle having a vehicle frame and elongate rail members mounted therewith. A tool frame is provided to which is coupled a tool attachment such as an offset arrangement of spiral bladed reel mower cutting units. The tool frame includes bars which shiftably engage the rails along the length of the elongate rails, and the rails support the bars of the tool frame as the bars and tool frame shift linearly within the rails. The tool frame shifts between a retracted operating position whereat the cutting units are in an operating position in close proximity to the vehicle, and an extended maintenance position whereat the cutting units are shifted outwardly from the vehicle frame for providing access to the cutting units. The bars are received within the respective rails and are shiftable therein in telescoping fashion. When the cutting units are in the operating position one of the cutting units is at least partially within the boundary of the vehicle.
The rails are oriented at an angle to a surface of the ground, and the tool frame shifts generally along the rails upwardly and outwardly away from the vehicle as the tool frame shifts to the extended maintenance position.
The rails according to the preferred embodiment extend generally longitudinally in the direction of vehicle travel and the tool frame is shiftable along the rails generally longitudinally in the direction of vehicle travel. A linear actuator or hydraulic cylinder engages one of the bars of the tool frame for shifting the tool frame between the extended and retracted positions.
A plurality of toothed wheels are provided in engagement with respective toothed rack members fixed with the bars. The wheels are fixed with a shaft supported by the vehicle, and the wheels and shaft rotate in unison to synchronize the shifting of the bars with respect to the rails.
A support is mounted with the vehicle frame and engages the tool frame in the retracted position for at least partially supporting the tool frame in the retracted position.
Each bar is movably carried within the rail between at least one lower and one upper support roller.
The present invention provides tool units located beneath the operating platform or the vehicle frame, and which can be displaced outwardly, i.e., beyond the contours of the lawn care vehicle. Consequently, the tool attachment is easily accessible to the operator. The tool may consist of a mower, e.g., a spiral-bladed or rotating blade lawn mower, a raking device, a clearing blade, a vertical cutter, a soil aerator, a manure spreader or the like. Depending on the position of the tool attachment, it may be practical to move said tool attachment outwardly from the front, the rear or the side of the vehicle in order to gain access.
Particular advantage is attained due to the use of an inclined guideway for the tool attachment on the vehicle frame. In this way, the tool attachment can not only be moved out of the area located underneath the lawn care vehicle, e.g., under a protective cover, under the vehicle frame, under an operating platform or the like, but also be raised such that it can be serviced even more easily.
The use of at least one bar according to the present invention that is movably accommodated in or on a rail of the vehicle frame represents a robust and simultaneously simple and inexpensive arrangement for carrying the tool attachment. A long guide way, e.g., a telescoping guide way, also helps prevent the occurrence of jams during movement.
If several offset tool units are provided, it is possible to arrange a central tool unit between adjacent tool units, i.e., offset toward the lawn care vehicle, so that the central tool unit occupies, for example, the space between two wheels. In this way, the structural length of the lawn care vehicle can be relatively short, i.e., the lawn care vehicle is more compact.
Within the spirit of the present invention, the adjustment of the frame may be carried out manually, with a mechanical winch or the like. When using heavy tool attachments, it is advantageous to carry out this adjustment by means of a motor that can preferably be remote-controlled.
Resistance against lateral forces can be achieved if the bar of the tool frame is movably arranged in a closed profile, i.e., a tube, wherein one or more longitudinal slots are provided in order to connect the motor if the motor is not arranged concentric with the bar or the rail. Alternatively, the bar may also be realized in the form of a tube, wherein the rail is realized in the form of a carrier, on which the tube is movably arranged.
The movement of two or more bars can be realized with the aid of only one motor if the respective bars are connected to one another such that they move synchronously and cannot become jammed. The shifting of the bars can be synchronized by a shaft to which geared wheels or friction wheels are fixed. The wheels can engage respective bars and by way of the shaft help insure that the bars shift together. Synchronous movement of the bars can be achieved since toothed wheels and toothed racks are used to lock the bars together, which results in no slippage.
The use of at least one abutment and at least one support on the tool attachment and the lawn care vehicle makes it possible to prevent the weight from affecting the steering when the tool attachment is retracted, i.e., in its normal position. In this way, shocks caused by uneven terrain are barely, if at all, introduced into the bars and rails.
A sensor may be provided in order to prevent accidents during the servicing of the tool attachment. This sensor detects when the tool attachment is moved out of its operating position, i.e., that the tool attachment is presumably moved into its maintenance and service position. This sensor may be coupled to motors for driving and/or retracting and/or pivoting the tool attachment by means of simple electrical or electronic switching elements or a computer-assisted control unit, in such a way that the motors are prevented from being activated when the tool attachment is out of its operating position.
According to an additional feature, a mechanical locking device that is manually actuated may be provided. This locking device secures the tool attachment to the vehicle frame when it is not in its operating position. This may be simply realized by means of a bolt that is inserted through aligned openings in the tool attachment and the vehicle frame.
If the tool attachment contains three spiral-mower tool units that are movably held on the tool frame in overlapping fashion, and if the outer tool units can be vertically pivoted into an idle position, the outer tool units will not only be easier to access because they are able to assume a vertical orientation, but they will also be able to be maintained or serviced in a narrow garage.
The bar is guided with little resistance to movement by means of a lower support roller and an upper support roller between the bar and the rail.